Wei Huan, Wu Fei, Li Lijuan, Yang Xiaoti, Xu Cong, Yu Ping, Ma Furong, Mao Lanqun
Beijing National Laboratory for Molecular Sciences, Key Laboratory of Analytical Chemistry for Living Biosystems, Institute of Chemistry, The Chinese Academy of Sciences, Beijing 100190, China.
University of Chinese Academy of Sciences, Beijing 100049, China.
Anal Chem. 2020 Aug 18;92(16):11374-11379. doi: 10.1021/acs.analchem.0c02240. Epub 2020 Jul 28.
Probing chemical information in the central nervous system is essential for understanding the molecular mechanism of brain function. Electrochemistry with tissue-implantable carbon fiber electrodes (CFEs) provides a powerful tool for monitoring the dynamics of neurochemicals in a subsecond time scale; however, the implantation of CFEs into brain tissue immediately causes the nonspecific adsorption of proteins on electrode surfaces. This process can dramatically impact the performance of the electrochemical method in terms of reduced sensitivity and accuracy. Herein, we report a strategy to minimize the electrode biofouling by masking CFEs with leukocyte membranes (LMs). We find that the LM masking endows CFEs with a highly hydrophilic surface that gains a high resistance to nonspecific protein adsorption. The electrode reactivity to target molecules decreases by a small degree due to the membrane coating, but the sensitivity loss of the LM-masked CFEs is greatly lessened even after implantation for 8 h. This study offers a new method of microelectrode modification by natural cell membranes for sustained sensing performance during long-term analysis.
探究中枢神经系统中的化学信息对于理解脑功能的分子机制至关重要。使用可植入组织的碳纤维电极（CFE）进行电化学分析，为在亚秒级时间尺度上监测神经化学物质的动态变化提供了一个强大的工具；然而，将CFE植入脑组织会立即导致蛋白质在电极表面的非特异性吸附。这个过程会在灵敏度和准确性降低方面极大地影响电化学方法的性能。在此，我们报告一种通过用白细胞膜（LM）覆盖CFE来最小化电极生物污染的策略。我们发现，LM覆盖赋予CFE高度亲水的表面，使其对非特异性蛋白质吸附具有高抗性。由于膜涂层，电极对目标分子的反应性略有降低，但即使在植入8小时后，LM覆盖的CFE的灵敏度损失也大大减轻。这项研究提供了一种通过天然细胞膜对微电极进行修饰的新方法，以在长期分析过程中保持传感性能。
